Optical networks can comprise a plurality of network nodes or network devices which are connected to each other via optical fibers. The network devices can comprise switches and routers used to forward optical signals from a source network node to a destination network node. Pluggable modules can be used to connect two network devices via optical cables. Optical signals transported via optical fibers are converted into electrical signals to be processed by data processing means of the receiving network device. For instance, the optical network can comprise a plurality of network devices manufactured by different producers and including different technical functions with a wide variety of different network devices using different internal signal formats for data processing. Pluggable modules can be plugged into sockets of a host board of a network device to connect the network device with another network device via an optical cable comprising one or more optical fibers. However, the available space on a host board of a network device is limited so that the number of available sockets of a host board of a network device is also restricted. Since different network devices can use different signal formats and comprise only a limited number of sockets to receive pluggable modules, the flexibility to set up an optical network is low and in some scenarios, it can become difficult or even impossible to connect two network devices of an optical network to each other because of the different used signal formats and the limited number of available sockets. Accordingly, there is a need to provide a pluggable module for an optical network which increases the flexibility to set up an optical network.